Yes, at the supermarket, gay bar, Costco, walking around the neighborhood, etc. I always say hi but they politely wait for me to say it first.
They're discreet. I guess some folks don't acknowledge them in a public place.
Answering your question about "recognizing" someone I know is an escort yet I never met him in person: Yes I have and usually their pics online look better than the guy looks in person. I guess we all have good and bad picture and we all select which ones we want to post on Facebook, Instagram, RM, etc.